Mobile storage systems have long been utilized to store documents, books and other items in a high density manner that also allows for easy access to the items contained on any portion of the mobile storage system. These systems typically include a number of storage units movably mounted on rails that are secured to the floor of a room or other enclosure. By operation of a motive system associated with each of the storage units, individual units may be moved along the rails to expose a desired unit in order to retrieve the items contained therein.
The motive system selected for these types of storage units can be either a mechanical system or an electrical system. With a mechanical motive system, each storage unit is moved by manually activating the mechanical mechanism, such as a hand crank. The crank or other manual activation means is disposed directly on the individual storage unit, and is mechanically connected to wheels on the storage unit to move those wheels and the storage unit along the rails.
With regard to the electrical motive systems used for the storage units, the system is activated by utilizing a switch that is operably connected to an electrically-powered motor connected to wheels for the storage unit. The activation of the motor then causes the wheels of the storage unit to rotate in the selected direction to move the storage unit in the desired direction.
A number of safety devices have been developed for use with mobile storage systems in order to prevent adjacent storage units from inadvertently being moved towards one another when a person or other object is positioned between the storage units. Many prior art safety devices designed for use with storage units in storage systems of this type are electrically operated safety devices that are integrated with a motor-operated drive system that moves the individual storage units along the rails during operation of the system.
While safety devices of this type function satisfactorily, it is necessary to supply electrical power to the storage unit in order to power the safety device. This is not a concern in a motor-operated systems, since each storage unit is supplied with electrical power in order to power the motor-operated drive system, unless there is a loss of power. When power is lost, however, the motor also ceases to function such that the storage unit is unable to move.
In mobile storage systems that have a mechanical drive system, the motive power is manually supplied by a user. As such, systems of this type do not require the supply of electrical power to the storage units so that the electrically powered-safety devices are not able to be utilized effectively. In particular, in those situations where the power supply to the electrical safety device is interrupted, unlike those storage units where the unit is moved by an electrically-powered motor, the manual input still enables the storage unit to move as directed by an individual, which can result in an unsafe condition.
As a result, it is desirable to develop a safety braking device for a storage units used in a mobile storage system that, while capable of providing the desired safety braking feature to the individual units within the storage system, does not require electrical power and also has a relatively simple construction for easy incorporation with the storage units, whether mechanically or electrically operated.